CVE-2026-55102hashi-vault-js is a Node.js module for interacting with the HashiCorp Vault API. Prior to 0.5.2, every API method in src/Vault.js passes failed requests through parseAxiosError(), which rethrows the raw AxiosError while retaining AxiosError.config and the equivalent response configuration. These objects can contain the X-Vault-Token request header and err.config.data request body, including submitted passwords or secret values. When a consuming application records the caught exception through console logging, structured loggers, monitoring, crash reporting, or an application performance monitoring service, the live Vault token and request secrets can be stored in plaintext and exposed to anyone with access to that output. A stolen token can permit unauthorized access to the Vault instance under the token's policies. This issue is fixed in version 0.5.2.